Backed out 2 changesets (bug 1685055) for nsWaylandDisplay related bustage CLOSED TREE

Backed out changeset 813da913ec72 (bug 1685055)
Backed out changeset c46c76db0a48 (bug 1685055)

gfx/thebes/gfxPlatform.cpp

@@ -83,6 +83,10 @@
 #  include "mozilla/WindowsVersion.h"
 #endif
 
+#ifdef MOZ_WAYLAND
+#  include "mozilla/widget/nsWaylandDisplay.h"
+#endif
+
 #include "nsGkAtoms.h"
 #include "gfxPlatformFontList.h"
 #include "gfxContext.h"
@@ -1349,6 +1353,10 @@ void gfxPlatform::ShutdownLayersIPC() {
   }
   sLayersIPCIsUp = false;
 
+#ifdef MOZ_WAYLAND
+  widget::WaylandDisplayShutdown();
+#endif
+
   if (XRE_IsContentProcess()) {
     gfx::VRManagerChild::ShutDown();
     // cf bug 1215265.

widget/gtk/WindowSurfaceWayland.cpp

@@ -14,6 +14,8 @@
 #include "gfxPlatform.h"
 #include "MozContainer.h"
 #include "nsTArray.h"
+#include "base/message_loop.h"  // for MessageLoop
+#include "base/task.h"          // for NewRunnableMethod, etc
 #include "mozilla/ScopeExit.h"
 #include "mozilla/StaticPrefs_widget.h"
 

widget/gtk/nsWaylandDisplay.cpp

@@ -25,13 +25,42 @@ namespace widget {
 static RefPtr<nsWaylandDisplay> gWaylandDisplays[MAX_DISPLAY_CONNECTIONS];
 static StaticMutex gWaylandDisplayArrayWriteMutex;
 
-// Dispatch events to Compositor/Render queues
-void WaylandDispatchDisplays() {
-  MOZ_ASSERT(NS_IsMainThread(),
-             "WaylandDispatchDisplays() is supposed to run in main thread");
+void WaylandDisplayShutdown() {
   for (auto& display : gWaylandDisplays) {
     if (display) {
-      display->DispatchEventQueue();
+      display->ShutdownThreadLoop();
+    }
+  }
+}
+
+static void DispatchDisplay(RefPtr<nsWaylandDisplay> aDisplay) {
+  // We can't use aDisplay directly here as it can be already released.
+  // Instead look for aDisplay in gWaylandDisplays and dispatch it only when
+  // it's still active.
+  for (auto& display : gWaylandDisplays) {
+    if (display == aDisplay) {
+      aDisplay->DispatchEventQueue();
+      return;
+    }
+  }
+  NS_WARNING("DispatchDisplay was called for released display!");
+}
+
+// Each thread which is using wayland connection (wl_display) has to operate
+// its own wl_event_queue. Main Firefox thread wl_event_queue is handled
+// by Gtk main loop, other threads/wl_event_queue has to be handled by us.
+//
+// nsWaylandDisplay is our interface to wayland compositor. It provides wayland
+// global objects as we need (wl_display, wl_shm) and operates wl_event_queue on
+// compositor (not the main) thread.
+void WaylandDispatchDisplays() {
+  for (auto& display : gWaylandDisplays) {
+    if (display) {
+      MessageLoop* loop = display->GetThreadLoop();
+      if (loop) {
+        loop->PostTask(NewRunnableFunction("WaylandDisplayDispatch",
+                                           &DispatchDisplay, display));
+      }
     }
   }
 }
@@ -184,9 +213,7 @@ static const struct wl_registry_listener registry_listener = {
     global_registry_handler, global_registry_remover};
 
 bool nsWaylandDisplay::DispatchEventQueue() {
-  if (mEventQueue) {
-    wl_display_dispatch_queue_pending(mDisplay, mEventQueue);
-  }
+  wl_display_dispatch_queue_pending(mDisplay, mEventQueue);
   return true;
 }
 
@@ -230,10 +257,22 @@ void nsWaylandDisplay::SyncBegin() {
   wl_display_flush(mDisplay);
 }
 
+static void WaylandDisplayQueueSyncBegin(RefPtr<nsWaylandDisplay> aDisplay) {
+  for (auto& display : gWaylandDisplays) {
+    if (display == aDisplay) {
+      display->SyncBegin();
+      return;
+    }
+  }
+  NS_WARNING("DispatchDisplay was called for released display!");
+}
+
 void nsWaylandDisplay::QueueSyncBegin() {
-  NS_DispatchToMainThread(
-      NS_NewRunnableFunction("nsWaylandDisplay::QueueSyncBegin",
-                             [this]() -> void { this->SyncBegin(); }));
+  MessageLoop* loop = GetThreadLoop();
+  if (loop) {
+    loop->PostTask(NewRunnableFunction("WaylandSyncBegin",
+                                       &WaylandDisplayQueueSyncBegin, this));
+  }
 }
 
 void nsWaylandDisplay::WaitForSyncEnd() {
@@ -243,8 +282,6 @@ void nsWaylandDisplay::WaitForSyncEnd() {
   }
 
   while (mSyncCallback != nullptr) {
-    // TODO: wl_display_dispatch_queue() should not be called while
-    // glib main loop is iterated at nsAppShell::ProcessNextNativeEvent().
     if (wl_display_dispatch_queue(mDisplay, mEventQueue) == -1) {
       NS_WARNING("wl_display_dispatch_queue failed!");
       SyncEnd();
@@ -257,8 +294,23 @@ bool nsWaylandDisplay::Matches(wl_display* aDisplay) {
   return mThreadId == PR_GetCurrentThread() && aDisplay == mDisplay;
 }
 
+class nsWaylandDisplayLoopObserver : public MessageLoop::DestructionObserver {
+ public:
+  explicit nsWaylandDisplayLoopObserver(nsWaylandDisplay* aWaylandDisplay)
+      : mDisplay(aWaylandDisplay){};
+  virtual void WillDestroyCurrentMessageLoop() override {
+    mDisplay->ShutdownThreadLoop();
+    mDisplay = nullptr;
+    delete this;
+  }
+
+ private:
+  nsWaylandDisplay* mDisplay;
+};
+
 nsWaylandDisplay::nsWaylandDisplay(wl_display* aDisplay, bool aLighWrapper)
-    : mThreadId(PR_GetCurrentThread()),
+    : mThreadLoop(nullptr),
+      mThreadId(PR_GetCurrentThread()),
       mDisplay(aDisplay),
       mEventQueue(nullptr),
       mDataDeviceManager(nullptr),
@@ -278,6 +330,11 @@ nsWaylandDisplay::nsWaylandDisplay(wl_display* aDisplay, bool aLighWrapper)
   }
 
   if (!NS_IsMainThread()) {
+    mThreadLoop = MessageLoop::current();
+    if (mThreadLoop) {
+      auto observer = new nsWaylandDisplayLoopObserver(this);
+      mThreadLoop->AddDestructionObserver(observer);
+    }
     mEventQueue = wl_display_create_queue(mDisplay);
     wl_proxy_set_queue((struct wl_proxy*)mRegistry, mEventQueue);
   }
@@ -293,6 +350,8 @@ nsWaylandDisplay::nsWaylandDisplay(wl_display* aDisplay, bool aLighWrapper)
   }
 }
 
+void nsWaylandDisplay::ShutdownThreadLoop() { mThreadLoop = nullptr; }
+
 nsWaylandDisplay::~nsWaylandDisplay() {
   wl_registry_destroy(mRegistry);
   mRegistry = nullptr;

widget/gtk/nsWaylandDisplay.h

@@ -75,11 +75,15 @@ class nsWaylandDisplay {
       zwp_primary_selection_device_manager_v1* aPrimarySelectionDeviceManager);
   void SetIdleInhibitManager(zwp_idle_inhibit_manager_v1* aIdleInhibitManager);
 
+  MessageLoop* GetThreadLoop() { return mThreadLoop; }
+  void ShutdownThreadLoop();
+
   bool IsExplicitSyncEnabled() { return mExplicitSync; }
 
  private:
   ~nsWaylandDisplay();
 
+  MessageLoop* mThreadLoop;
   PRThread* mThreadId;
   wl_display* mDisplay;
   wl_event_queue* mEventQueue;
@@ -97,6 +101,7 @@ class nsWaylandDisplay {
 };
 
 void WaylandDispatchDisplays();
+void WaylandDisplayShutdown();
 void WaylandDisplayRelease();
 
 RefPtr<nsWaylandDisplay> WaylandDisplayGet(GdkDisplay* aGdkDisplay = nullptr);